Stilll Running Too Warm

[kodioneill]

Originally Posted by ruwoodbury

I'm typically at 4,400-5,200. It's funny because Steve Wong saw my dyno file and thought everything looked okay. I could put the stock chip back in to check temps. I'm leaning (no pun intended) to the too lean theory. Is there a way to adjust the mixture outside of re-programming the chip?

You can change the idle mixture at the air flow meter but there is no changing the timing like a earlier poster thought.

[kodioneill]

[QUOTE=ruwoodbury;7644394]Thanks. The engine was out for a clutch, etc. and didn't run warm prior to that. I had the mechanic check for obstructions when he changed the thermostat.[/QUOTE

I wouldn't be chasing problems until you retrace the clutch job and see if you
created a problem since the overheating started "after " the clutch job.

[Reiver]

If your dyno CO numbers are correct I'd be changing that CO no matter what.....even if that was not the primary issue.

[JAR0023]

Random thoughts.

I don't think anyone has mentioned the external thermostat. Just like the internal one it could be not opening fully.

With Motronic you have idle maps, part throttle maps, full throttle maps. You can make air/fuel adjustments on the AFM but you are really only affecting the idle maps. Part throttle and full throttle are controlled by the chip.

O2 sensor is working in the idle and part throttle maps giving feedback to the DME to bring the car back to lamba 1.0 or 14.7. I don't know what the default in on the O2 sensor if it fails. Meaning if it has failed I don't know if it's telling the DME to go lean or rich. I'm sure someone will chime in.

Assuming the car ran well when the chip was installed and now doesn't. The chip hasn't changed. It could be low fuel pressure causing the lean condition. DME tells the injectors to open for a specified time. Less fuel pressure, less fuel into the engine. Weak pump, clogged fuel filter, bad fuel pressure regulator could all lower fuel pressure. There is a vacuum line running to the fuel pressure regulator but it works by pulling the pressure down. A vacuum leak here should result in too much fuel. You could have a clogged or malfunctioning injector, but to me, you would notice rough running if this was the case. -J

[ruwoodbury]

I'm going to reinstall the stock chip this morning and see what the temps look like. Unfortunately, for this purpose, the daytime temps are forecast for the low 80s. As things are I would still expect oil temps at or above 200f. If it's 10-20 degrees less than I think I can assume a lean running condition from the custom chip.
I also plan to give Steve Wong a call later and discuss the chip settings with him as well.
If it's not the chip I can take a look at fuel delivery/pressure.
kodioneill,
What kind of things might be affecting the oil temps related to a clutch replacement? The internal thermostat was bad and replaced earlier this summer. The clutch was replaced by my mechanic.

[ruwoodbury]

I just took a 45 minute drive with the stock installed. Over the pass and down through a twisty canyon road, then back up on the freeway through another canyon and home. Temps here in the low 60s, in the valley mid-to-upper-60s. Oil temp topped out a little above the 210f line. Too warm! I'm going to reinstall the SW chip and take a similar run shortly and compare.
Maybe the SW chip isn't running lean after all.

[ruwoodbury]

Took a run with the SW chip and got the same oil temps, 210f+, as with the OEM chip--and is a little higher outside temps (still only mid 70s at most). If it's lean running, it's not the chip. Stopped by my mechanic to discuss it and he's going to check for vacuum leaks and fuel pressure values on Friday. Don't know what to make of the fan thermostat triggering the fan at 220f instead of the 200f it's supposed to (it's the BMW unit that some people have installed to help with high temps).
Any other ideas out there? I'm all ears.
Thanks

[JAR0023]

Where are you measuring the 220*? If 220* at the engine it's possible the oil is only 200* by the time it gets to the aux oil cooler up front.

I chased high temps with my car earlier this summer. I made a bunch of measurements with an IR temp gun. I don't remember specifics but there is definitely a temp drop between the oil line going from engine to external thermostat and the external line leading to the cooler in the front wheel well.

Re-read your original post. You said you replaced the spring in the external thermostat. The spring closes the thermostat. Did you test the plunger to see that is was opening all the way. Boil it in water, should be open by 190*.

The added fan helps at low speeds but doesn't help much on the highway. How's the seal around the cooler? You need that in place or air will flow around the cooler at speed.

You can also make a block off for the bottom of the car to keep air that enters from the bumper from going under the car. I used a $8 sheet of 1/8" ABS cut in basically a quarter circle shape to block off the area. Bolts to the bottom mount of the cooler and follows the contour of the front bumper. Any air going into that area is forced through the cooler.

One more thing I did that worked for me is add the cooler scoop that takes the place of the marker light. I'm sure someone will be along shortly to tell me it won't work but it did on my car. Combine the scoop with sealing up the cooler and I saw a 15*-20* drop on the highway. I don't have a fan so temps creep up in traffic but I don't see much stop and go and the temps fall right back down once I'm up to speed.

My car is fine until the temps hit 90*. At the beginning of the summer my car would go straight to 225-230* and creep up over 240*. Now it goes to 210* and might creep up to 225* in traffic. -J

[ruwoodbury]

JAR0023,
Thanks. I'm measuring at the oil temp sening unit which matches what I'm seeing on the gauge. I'll have the mechanic check the external thermostat. I also had him install a new seal around the cooler early on. Your block plate sounds interesting. Does the leading edge fit above the fog lamps?
I would be happy with 210f in the 90s.

[JAR0023]

I'll see if I can get an on car photo this weekend. I'll post a photo of my rough template below. To answer your question, no. I have the block off plate wedged in at the bottom lip of the valance where it curls back. In the photo you are looking at what would be the bottom side of the block off.

The louvered cooler guard hangs below the bottom cooler mount. The back edge of my block off buts up against the louvered guard and uses the mount bolts to hold it in place. The curved front edge is tight against the back of the lower valance panel. The curve carries around to the guard for the A/C condenser. I have a couple of large zip ties holding the block off to the condenser guard. On the inside edge I followed whatever profile that kept the block off flat. I made a template with cereal box and bought the ABS sheet from Amazon. IIRC one of my horns hung down pretty low and I had to bend up the upper mount a bit for clearance. -J

[ruwoodbury]

How exactly does one boil the external thermostat and the observe it opening? It's a big chunk and the actual valve is enclosed.

[JAR0023]

Originally Posted by ruwoodbury

How exactly does one boil the external thermostat and the observe it opening? It's a big chunk and the actual valve is enclosed.

Bad wording on my part. Remove the insert that goes into the thermostat along with the spring. Barrel shaped has a plunger on one end. Should start opening around 180 and be all the way open by 190. Let me see if I can find the post with photos. -J

There is post that I can't find showing photos of good and bad thermostat plungers side by side. Here are a couple of other links.

Thermostat Valve Opening Test....

Thermostatic oil plunger end-plug removal...?

Here it is. Google image search is your friend.

overheating mystery

[JAR0023]

Couple of snaps of my block off plate. -J

[ruwoodbury]

Okay, the latest now is I've had the fuel pressure checked, everything's fine. No vacuum leaks either. In checking my records, last year I had the external oil thermostat replaced along with the spring. Everything's checking out normal except the warmer oil temps. Last evening with outside temps in the 60s and a steady rain the oil went right up to a little over the 210f mark again.
Maybe I just need to increase cooling capacity at this point. Any other ideas out there?

[911SauCy]

Ok. Don't take this to the bank as I am by no means a professional mechanic.

However, I recently had Musante Motorsports here in CT (love those guys) do a valve adjustment among many other odds and ends...and we discovered a screw-up on exhaust side of #2. Aside from the things you have already tracked down and eliminated, we discussed the potential for a high leak-down number/cylinder mess-up causing hotter temps.

I have been thinking about this since and can't really understand how it would contribute to higher oil temps...but the pros mentioned it.

Wuld be interested to hear other feedback on this.

[ruwoodbury]

Thanks. I had a valve adjustment and leak down test last spring and everything looked good.
Everything in the oil cooling system has been checked, cleaned or replaced in the past year. Again, it never overheats it just runs warm. What set this thread off was the 230f+ temp last week where I had seen temps 10 degrees cooler at most in higher outside temps. I'm thinking of building a block off plate like JAR0023s. I have DE next week and expect the temp to be 80+, so I'll see how it reacts to hard running in moderate conditions.

[911SauCy]

Originally Posted by ruwoodbury

Thanks. I had a valve adjustment and leak down test last spring and everything looked good.
Everything in the oil cooling system has been checked, cleaned or replaced in the past year. Again, it never overheats it just runs warm. What set this thread off was the 230f+ temp last week where I had seen temps 10 degrees cooler at most in higher outside temps. I'm thinking of building a block off plate like JAR0023s. I have DE next week and expect the temp to be 80+, so I'll see how it reacts to hard running in moderate conditions.

My car as well, never overheats but warms up quickly, and runs about 20deg hotter than it should.

I also had a valve adj 3/12 and leak down, all was well. When car was at the shop strange noise from driver side bank of cyl lead me to have them investigate.

Almost everything under the valve cobers needed to be retorqued, #2 exh was all messed up @ 45% leakdown. Was 3% last spring. Car was NEVER over-reved, mistreated, etc

God willing it will get better on its own and this is not your problem, but just an fyi of my recent travels

[ClickClickBoom]

Originally Posted by ruwoodbury

Do you think the open right side SSI could have something to do with it? It's connected at the front but open at the rear.

Yes!
This is your problem......
Occams Razor, was the right side heat exchanger hooked up prior to the engine drop?

[Lapkritis]

Originally Posted by ClickClickBoom

Yes!
This is your problem......
Occams Razor, was the right side heat exchanger hooked up prior to the engine drop?

X2

What is the engine shroud outlet doing on that side? Just blowing into the engine compartment?

[Dodge Man]

Originally Posted by ruwoodbury

I'm typically at 4,400-5,200. It's funny because Steve Wong saw my dyno file and thought everything looked okay. I could put the stock chip back in to check temps. I'm leaning (no pun intended) to the too lean theory. Is there a way to adjust the mixture outside of re-programming the chip?

My only overheating problems came from masking paper from a body shop caked on top of the BHER. Resolved with lots of Simple Green & a garden hose. However, you may want to put the stock chip back in to troubleshoot the mechanical cooling components. Go back to the last known "good" condition and then carefully add the changes for analysis. Also, get a IR thermometer to see how accurate your "Oil Temp" gage reads. Best of luck.